Ovarian Cancer (OC) and its management

Ovarian cancer is the second most common gynaecological cancer in the western world, and the leading cause of death from gynaecological malignancies [Dinh 2008]. Its estimated crude incidence in the European Union is close to 18/100,000 women/year and the mortality reaches 12/100,000 women/year [Vasey 2005]. Approximately 30,000 women die annually from ovarian cancer in Europe [Ferlay 2002]. Most of these cases affect women older than 50 years, and epithelial tumours account for over 90% of all ovarian cancers [Salzberg 2005; Colombo 2006].

Staging is described using the American Joint Committee on Cancer (AJCC) and the Federation Internationale de Gynecologie et d’Obstetrique (FIGO) classification guidelines (Table 1).

Approximately 75% of the cases present an advanced stage at the moment of the diagnosis due to the absence of overt signs or symptons in earlier-stage disease [Dinh 2008, Ozols 2005].

The mortality rate of ovarian cancer has slightly changed within the last 50 years, and long-term trends in cancer mortality reveal few encouraging advances in overall survival, possibly favoured by improved surgery and the use of new active drugs [Ferlay 2002].

Surgery can be curative when the disease is still confined to the ovary, and in these cases 5-year survival rates exceed 90%. However, as most patients present with intraperitoneal dissemination, survival rates drop to 20-25% [Ozols 2005]. Current standard primary therapy for advanced ovarian cancer involves maximal cytoreductive surgery followed by systemic platinum-based chemotherapy -usually carboplatin- combined with a taxane [Ozols 2005; Salzberg 2005; Colombo 2006; du Bois 2005]. Up to 80% of women with stage III/IV tumours respond to therapy, and 50% achieve a complete response. Despite these high initial response rates, results still remain far from satisfactory, as median time to progression (TTP) does not exceed 15-18 months, median survival is below 3 years, and 5-year survival rates are close to 30% [Vermorken 2008]. Furthermore, a large proportion of responding patients (50-75%) eventually relapse [Vermorken 2008].

Table 1. American Joint Committee on Cancer (AJCC) TNM and FIGO Staging System for Ovarian and Primary Peritoneal Cancer (7th ed., 2010)

Primary Tumour (T)
TNM FIGO TNM FIGO
TX Primary tumour cannot be assessed T3 III Tumour involves one or both ovaries with microscopically confirmed peritoneal metastasis outside the pelvis
T0 No evidence of primary tumour T3a IIIA Microscopic peritoneal metastasis beyond pelvis (no macroscopic tumour)
T1 I Tumour limited to ovaries (one or both) T3b IIIB Microscopic peritoneal metastasis beyond pelvis 2 cm or less in greatest dimension
T1a IA Tumour limited to one ovary; capsule intact, no tumour on ovarian surface. No malignant cells in ascites or peritoneal washings T3c IIIC Peritoneal metastasis beyond pelvis more 2 cm in greatest dimension and/or regional lymph node metastasis
T1b IB Tumour limited to both ovaries; capsules intact, no tumour on ovarian surface. No malignant cells in ascites or peritoneal washings Regional Lymph Nodes (N)
T1c IC Tumour limited to one or both ovaries with any of the following: capsule ruptured, tumour on ovarian surface, malignant cells in ascites or peritoneal washings NX Regional lymph nodes cannot be assessed
T2 II Tumour involves one or both ovaries with pelvic extension N0 No regional lymph node metastasis
T2a IIA Extension and/or implants on uterus and/or tube(s). No malignant cells in ascites or peritoneal washings N1 IIIC Regional lymph node metastasis
T2b IIB Extension to and/or implants on other pelvic tissues. No malignant cells in ascites or peritoneal washings Distant Metastasis (M)
T2c IIC Pelvic extension and/or implants (T2a or T2b) with malignant cells in ascites or peritoneal washings M0 No distant metastasis
M1 IV Distant metastasis (excludes peritoneal metastasis)
Note: Liver capsule metastasis is T3/Stage III; liver parenchymal metastasis, M1/Stage IV. Pleural effusion must have positive cytology for M1/Stage IV.

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